1. Field of the Invention
The present invention is directed to an engine mount for a watercraft, and more particularly, to an engine mount for a watercraft having an engine that is vertically oriented.
2. Description of Related Art
The design of watercraft, and particularly the engine compartment and the passengers"" area thereof, presents considerable challenges to the designer, particularly in the class of watercraft that is designed primarily to accommodate a relatively few number of people (for example, eight or less passengers). The watercraft should be designed so as to provide comfortable seating for each passenger. In addition, each passenger should be seated in a position which allows the passenger to enjoy the view without obstructions from the others. The watercraft should also include storage compartments for carrying paraphernalia used by boaters, such as coolers, beverages, food, water skiing equipment, and other such items.
One type of watercraft which is becoming relatively popular is the so-called xe2x80x9copen bowxe2x80x9d or xe2x80x9cbow riderxe2x80x9d type of watercraft. This type of watercraft typically includes a main passengers"" compartment positioned at approximately midship in which the operator""s control position is located. The bow of the watercraft is provided with a further passengers""area. Alternatively, the bow of the watercraft may include a small cabin which may have a seat and/or a head.
For convenient and efficient hull configuration, however, the bow area generally tapers inwardly toward the tip or nose of the bow. Thus, the foot area for passengers seated in the bow area can be restricted. With this type of watercraft, it is also desirable to permit access between the two passengers"" areas without the rider having to climb over a portion of the hull which separates the two areas. Passthroughs can be provided between the main and bow passengers"" areas, but these passthroughs then restrict the available seating area in the bow portion, as well as its effectiveness.
The rear or xe2x80x9caftxe2x80x9d of an inboard/outboard engine-powered the watercraft typically includes an engine compartment positioned behind the passengers"" areas. The engine compartment may or may not extend over the entire width of the watercraft.
Of course, accommodating each of the above areas, compartments, and considerations can be met by merely making the size of the watercraft larger. However, as the size of the watercraft is increased, the weight is also increased. In particular, the overall length of a watercraft is a critical dimension which affects the overall weight of the watercraft. As the weight of the watercraft increases, so does the power required to drive it, as well as the cost of the watercraft itself and the difficulty in transporting the watercraft from one location to another.
A need therefore exists for a watercraft which minimizes the overall length of the engine compartment, thus allowing the overall length and size of the watercraft to be minimized. It is desirable that the engine compartment configuration does not comprise the comfort of the passengers"" areas.
According to one aspect of the present invention, a watercraft includes at least one passengers"" area and an engine compartment positioned rearward from the passengers"" area and including at least one internal combustion engine. The internal combustion engine is arranged such that its crankshaft is vertically oriented. The gear box which connects the crankshaft of the engine to a propulsion unit, is arranged at least partially beneath the engine. Arranged as such, the overall length, i.e., along a longitudinal axis of the hull of the watercraft, is minimized, since the gear box is located at least partially beneath the engine.
One aspect of the present invention includes the realization that the engine compartments of some watercraft can accommodate vertically oriented engines. For example, a hull of a small watercraft which includes a passengers"" are with at least two seats in a side-by-side relationship in a passengers"" area typically has a height which allows passengers to sit in the passengers"" area and be protected by the side walls or bulwarks of the hull while in a seated position. Thus, the maximum overall height of an engine compartment arranged behind the passengers"" area of a known watercraft may extend from a lower surface of the hull up to the upper edge of the bulwarks, without excessively increasing the overall height of the hull. Thus, by mounting an engine in an engine compartment such that the crankshaft of the engine extends vertically, the present invention allows the overall length of the engine compartment to be minimized. The reduction in the engine compartment length has a significant impact on the overall length of the watercraft and the size of the passengers"" areas. Thus, by providing an engine mount as such, the overall weight and the resulting power-to-weight ratio of the watercraft is enhanced. Additionally, by minimizing the overall length of the engine compartment, additional space may be provided for storage compartments.
According to another aspect of the present invention, a watercraft includes an engine compartment and engine provided within the engine compartment. The engine includes an engine body having a crankshaft joumaled for rotation at least partially within the engine body and about a generally vertical axis. A gear box having an output shaft driven by the crankshaft, is provided beneath the engine. The watercraft also includes lubrication system which includes a lubricant reservoir and which is configured to circulate lubricant between the lubricant reservoir and at least one lubricant gallery provided within the engine body. The gear box forms at least a portion of the lubricant reservoir.
By providing a gear box beneath the engine body which forms at least a portion of the lubricant reservoir, the watercraft according to the present invention efficiently utilizes the limited space available in engine compartments of watercaft. For example, as noted above, the size of the engine compartment affects the overall size, and thus the overall weight, of a watercraft. Therefore, by providing a gear box which provides the dual functions of journaling gears therein and providing a reservoir for the lubrication system, the watercraft according to the present invention reduces the overall size occupied by the engine and thus allows the overall size of the engine compartment as well as the watercraft itself, to be reduced.
According to a further aspect of the present invention, a watercraft includes a hull having an engine compartment and at least one internal combustion engine disposed within the engine compartment. The engine includes an engine body and a crankshaft journaled for rotation at least partially within the engine body. The engine body is oriented such that the crankshaft rotates about a generally vertical axis. The gear box is arranged at a lower end of the engine body and includes an output shaft which is driven by the crankshaft of the engine. The watercraft also includes an exhaust system having at least a first exhaust conduit, a portion of which passes through at least a portion of the gear box.
By arranging at least a portion of the exhaust system to pass at least partially through the gear box, the present invention provides enhanced flexibility in the design of the exhaust system. For example, the engine body can include an exhaust collector passage extending through the engine body to an exhaust outlet port provided at an interface between the engine body in the gear box. In this arrangement, a portion of the exhaust system extends between the exhaust outlet port and a side wall of the gear box. The remainder of the exhaust system extends from the side wall of the gear box to various down stream exhaust system components. Configured as such, the remainder of the exhaust system may be arranged in various arrangements which maximize the limited space available in the engine compartment of watercraft. For example, since the exhaust conduit passes through the gear box at a lower end of the engine, the remainder of the exhaust system may be routed deep within the engine compartment, thereby providing enhanced access to the other components attached to the engine body. Alternatively, the remainder of the exhaust system may be routed upward and over the top of the engine, thereby allowing the remainder of the exhaust system to be extended so as to enhance sound attenuation, while not excessively increasing a width of the engine.
Further aspects, features, and advantages of the present invention will become apparent from the detailed description of the preferred embodiment that follows.